Mobile x-ray apparatus

ABSTRACT

A mobile X-ray apparatus includes: an X-ray radiation device; a controller configured to control the X-ray radiation device; a power supply configured to supply operating power to the X-ray radiation device and the controller via a lithium ion battery and control overcurrent occurring during X-ray emission by the X-ray radiation device; and a charger configured to charge the power supply. Each of the controller, the power supply, and the charger is embodied in a physically separate module, and each of the power supply and the charger is encased in a metal case.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation application of U.S. patent application Ser. No.15/471,657, filed Mar. 28, 2017, in the U.S. Patent and TrademarkOffice, which claims priority from Korean Patent Application No.10-2017-0004164, filed Jan. 11, 2017, in the Korean IntellectualProperty Office. The disclosure of the above-named application isincorporated herein by reference in its entirety.

BACKGROUND 1. Field

The present disclosure relates to X-ray apparatuses including lithiumion batteries.

2. Description of the Related Art

X-rays are electromagnetic waves having wavelengths of 0.01 to 100angstroms (Å), and are widely used, due to their ability to penetrateobjects, in medical apparatuses for imaging the inside of a living bodyor in non-destructive testing equipment for industrial use.

An X-ray apparatus using X-rays may obtain X-ray images of an object bytransmitting X-rays emitted from an X-ray source through an object anddetecting a difference in intensities of the transmitted X-rays via anX-ray detector. The X-ray images may be used to examine an internalstructure of an object and diagnose a disease of the object. The X-rayapparatus facilitates observation of an internal structure of an objectby using a principle in which penetrating power of an X-ray variesdepending on the density of the object and atomic numbers of atomsconstituting the object. As a wavelength of an X-ray decreases,penetrating power of the X-ray increases and an image on a screenbecomes brighter.

Since an X-ray radiation device and an X-ray detector of the X-rayapparatus are generally affixed to a specific space, a patient needs tobe transferred to an examination room where the X-ray apparatus islocated for X-ray imaging.

However, it is difficult to use a general X-ray apparatus in the case ofperforming X-ray imaging examinations on patients with mobilityproblems. Thus, a mobile X-ray apparatus has been developed to performX-ray imaging without space limitations.

In the mobile X-ray apparatus, an X-ray radiation device is mounted on amovable main body, and a portable X-ray detector is used. Due to thisconfiguration, the mobile X-ray apparatus may be taken directly to apatient with reduced mobility in order to perform X-ray imaging.

Lead-acid batteries are generally inexpensive and are widely used inmobile X-ray apparatuses.

However, lead-acid batteries have a short life span (two years or 500cycles), are bulky and heavy, and may release hazardous materials intothe environment.

Furthermore, use of such bulky or heavy lead-acid batteries isinconvenient when trying to move an X-ray apparatus.

SUMMARY

Provided are mobile X-ray apparatuses including lithium ion batteriesthat have a relatively long life span, are small and lightweight, andare environmentally-friendly as they do not release hazardous materials,compared to lead-acid batteries.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to an aspect of an embodiment, a mobile X-ray apparatusincludes: an X-ray radiation device; a controller configured to controlthe X-ray radiation device; a power supply configured to supplyoperating power to the X-ray radiation device and the controller via alithium ion battery and control overcurrent occurring during X-rayemission by the X-ray radiation device; and a charger configured tocharge the power supply, wherein the controller, the power supply, andthe charger are each constituted by a physically separate module, andthe power supply and the charger are each encased in a metal case.

The power supply may include: the lithium ion battery; a batterymanagement system (BMS) circuit configured to detect a state of thelithium ion battery and control an operation of the power supply; adischarge field effect transistor (FET) configured to control theovercurrent and including a plurality of FETs connected in parallel; anda charge FET.

The discharge FET and the charge FET are further configured to control apath of a discharge current or a charge current when the lithium ionbattery is discharged or charged.

The BMS circuit is further configured to control an operation of aprotection circuit protecting against at least one of over-discharge,overcurrent, overheating, and unbalancing between cells in the lithiumion battery.

The power supply may further include a first current sensor and a secondcurrent sensor, and the BMS circuit is further configured to detect,during the X-ray emission by the X-ray radiation device, the overcurrentby activating the second current sensor.

The mobile X-ray apparatus may further include a current sensor locatedat an output terminal of the charger in order to detect a chargecurrent.

The controller, the power supply, and the charger may respectivelyinclude communication connectors, and the controller, the power supply,and the charger are configured to communicate with one another via thecommunication connectors according to a controller area network (CAN)protocol.

The power supply may include a temperature sensor configured to detect atemperature of the lithium ion battery, and the controller is furtherconfigured to directly monitor information about the temperaturedetected by the temperature sensor.

The power supply and the charger may respectively include interrupt pinsthat can be directly controlled by the controller, and the controller isfurther configured to respectively turn off the power supply and thecharger via the interrupt pins.

The power supply is further configured to receive data necessary toupdate firmware for the BMS circuit from the controller via thecommunication connector.

The power supply is further configured to receive, when the power supplyis connected to the controller via the communication connector, datanecessary to update firmware for the BMS circuit, from the controller.

The BMS circuit may include a master BMS circuit and a plurality ofslave BMS circuits, and each of the slave BMS circuits may be directlyconnected to the lithium ion battery to detect information about thestate of the lithium ion battery and transmit the detected informationto the master BMS circuit via a communication interface.

The lithium ion battery may include a plurality of cell groups, eachcell group having a plurality of lithium ion battery cells connected inparallel.

A battery pack may be formed by connecting the plurality of cell groupsof the lithium ion battery in series, and the battery pack may beconnected to each of the slave BMS circuits.

The lithium ion battery may include four lithium ion battery cells thatare connected in parallel to form a cell group.

The metal case of the power supply may include at least one handle.

A weight of the power supply may be less than or equal to 35 kilograms(kg).

A partition wall may be provided between the lithium ion battery and theBMS circuit.

Each cell in the lithium ion battery may be inserted into a holder madeof a flame retardant material.

The mobile X-ray apparatus may further include a frame that is attachedto a main body of the mobile X-ray apparatus via a hinge so as to becapable of pivoting around a hinge axis, and a system board may bemounted on the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings in which:

FIG. 1 illustrates an X-ray apparatus implemented as a mobile X-rayapparatus, according to an embodiment;

FIG. 2 illustrates an X-ray detector included in the X-ray apparatus ofFIG. 1;

FIG. 3 is a block diagram of an X-ray apparatus according to anembodiment;

FIG. 4 illustrates components of a power supply included in a mobileX-ray apparatus, according to an embodiment;

FIG. 5 is a schematic diagram illustrating discharging of a lithium ionbattery according to an embodiment;

FIG. 6 is a schematic diagram illustrating charging of a lithium ionbattery according to an embodiment;

FIG. 7 is a detailed block diagram of a mobile X-ray apparatus accordingto an embodiment;

FIG. 8 illustrates a shutdown process performed by a mobile X-rayapparatus according to an embodiment;

FIG. 9 illustrates a charger according to an exemplary embodiment;

FIG. 10 is a timing diagram of an operation of charging a lithium ionbattery according to an exemplary embodiment; and

FIG. 11 is a flowchart of a method of sensing of a low current state bya charger, according to an exemplary embodiment.

FIG. 12 illustrates an X-ray apparatus according to an embodiment;

FIG. 13 illustrates an X-ray apparatus, according to an embodiment;

FIG. 14 illustrates a state in which a power supply is detached from anX-ray apparatus, according to an embodiment;

FIG. 15 illustrates an X-ray apparatus according to an embodiment;

FIG. 16 illustrates a power supply according to an embodiment;

FIG. 17 is an example of a controller according to an embodiment;

FIG. 18 illustrates a charger according to an embodiment;

FIG. 19 illustrates a state in which a power supply, a controller, and acharger are connected to one another, according to an embodiment;

FIG. 20 illustrates a power supply according to an embodiment;

FIG. 21 is a cross-sectional view of a power supply according to anembodiment;

FIG. 22 is a block diagram of a configuration of a battery managementsystem (BMS) circuit according to an embodiment;

FIG. 23 shows a state in which a battery pack is mounted in a powersupply according to an embodiment;

FIG. 24 illustrates a structure of a battery pack according to anembodiment;

FIG. 25 illustrates a configuration of a slave BMS circuit according toan embodiment;

FIG. 26 illustrates a structure in which a system board is mounted on aside of an X-ray apparatus, according to an embodiment; and

FIG. 27 illustrates a state in which frames of FIG. 26 are open.

DETAILED DESCRIPTION

The present specification describes principles of the present disclosureand sets forth embodiments thereof to clarify the scope of the presentdisclosure and to allow those of ordinary skill in the art to implementthe embodiments. The present embodiments may have different forms andshould not be construed as being limited to the descriptions set forthherein.

Like reference numerals refer to like elements throughout. The presentspecification does not describe all components in the embodiments, andcommon knowledge in the art or the same descriptions of the embodimentswill be omitted below. The term “part” or “portion” used herein may beimplemented using hardware or software, and according to embodiments, aplurality of “parts” or “portions” may be formed as a single unit orelement, or one “part” or “portion” may include a plurality of units orelements. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items. Expressionssuch as “at least one of,” when preceding a list of elements, modify theentire list of elements and do not modify the individual elements of thelist. Hereinafter, the operating principles and embodiments of thepresent disclosure will be described in detail with reference to theaccompanying drawings.

In the present specification, an image may include a medical imageobtained by a magnetic resonance imaging (MRI) apparatus, a computedtomography (CT) apparatus, an ultrasound imaging apparatus, an X-rayapparatus, or another medical imaging apparatus.

Furthermore, in the present specification, an “object” may be a targetto be imaged and include a human, an animal, or a part of a human oranimal. For example, the object may include a body part (an organ,tissue, etc.) or a phantom.

FIG. 1 is an external view and block diagram of an X-ray apparatus 100implemented as a mobile X-ray apparatus, according to an embodiment.

Referring to FIG. 1, the X-ray apparatus 100 according to the presentembodiment includes an X-ray radiation device 110 for generating andemitting X-rays, an input device 151 for receiving a command from auser, a display 152 for providing information to the user, a controller120 for controlling the X-ray apparatus 100 according to the receivedcommand, and a communication unit 140, i.e., a communication device orinterface, for communicating with an external device.

The X-ray radiation device 110 may include an X-ray source forgenerating X-rays and a collimator for adjusting a region irradiatedwith the X-rays generated by the X-ray source.

When the X-ray apparatus 100 is implemented as a mobile X-ray apparatus,a main body 101 connected to the X-ray radiation device 110 is freelymovable, and an arm 103 connecting the X-ray radiation device 110 andthe main body 101 to each other is also rotatable and linearly movable.Thus, the X-ray radiation device 110 may be moved freely in athree-dimensional (3D) space.

The input device 151 may receive commands for controlling imagingprotocols, imaging conditions, imaging timing, and locations of theX-ray radiation device 110. The input device 151 may include a keyboard,a mouse, a touch screen, a microphone, a voice recognizer, etc.

The display 152 may display a screen for guiding a user's input, anX-ray image, a screen for displaying a state of and the like.

The controller 120 may control the X-ray apparatus 100, imagingconditions and imaging timing of the X-ray radiation device 110according to a control command input by the user and generate a medicalimage based on image data received from an X-ray detector 200.Furthermore, the controller 120 may control a position or orientation ofthe X-ray radiation device 110 according to imaging protocols and aposition of an object.

The controller 120 may include a memory configured to store programs forperforming the above operations of the X-ray apparatus 100 as well asoperations thereof that will be described below and a processor or amicroprocessor configured to execute the stored programs. The controller120 may include a single processor or a plurality of processors ormicroprocessors. When the controller 120 includes the plurality ofprocessors, the plurality of processors may be integrated onto a singlechip or be physically separated from one another.

A holder 105 may be formed on the main body 101 so as to accommodate theX-ray detector 200. Furthermore, a charging terminal is disposed in theholder 105 so as to charge the X-ray detector 200. In other words, theholder 105 may be used to accommodate and also to charge the X-raydetector 200.

The input device 151, the display 152, the controller 120, and thecommunication unit 140 may be provided on the main body 101. Image dataacquired by the X-ray detector 200 may be transmitted to the main body101 for image processing, and then the resulting image may be displayedon the display 152 or transmitted to an external device via thecommunication unit 140.

Furthermore, the controller 120 and the communication unit 140 may beseparate from the main body 101, or only some components of thecontroller 120 and the communication unit 140 may be provided on themain body 101.

The X-ray apparatus 100 may be connected to external devices such as anexternal server 31, a medical apparatus 32, and a portable terminal 33(e.g., a smart phone, a tablet PC, or a wearable device) in order totransmit or receive data via the communication unit 140.

The communication unit 140 may include at least one component thatenables communication with an external device. For example, thecommunication unit 140 may include at least one of a local areacommunication module, a wired communication module, and a wirelesscommunication module

Furthermore, the communication unit 140 may receive a control signalfrom an external device and transmit the received control signal to thecontroller 120 so that the controller 120 may control the X-rayapparatus 100 according to the received control signal.

Alternatively, by transmitting a control signal to an external devicevia the communication unit 140, the controller 120 may control theexternal device according to the transmitted control signal. Forexample, the external device may process data according to a controlsignal received from the controller 120 via the communication unit 140.

Furthermore, the communication unit 140 may further include an internalcommunication module that enables communications between components ofthe X-ray apparatus 100. A program for controlling the X-ray apparatus100 may be installed on the external device and may include instructionsfor performing some or all of the operations of the controller 120.

The program may be preinstalled on the portable terminal 33, or a userof the portable terminal 33 may download the program from a serverproviding an application for installation. The server for providing anapplication may include a recording medium having the program recordedthereon.

In addition, the main body 101 may be equipped with an alternatingcurrent (AC) power cord 750 and/or a switch 716. The user may connectthe AC power cord 750 to an outlet (not shown) when a battery managementsystem (BMS) is shut down to wake up the BMS from shutdown. Furthermore,the user presses the switch 716 when the BMS is shut down to wake up theBMS from shutdown.

FIG. 2 is an external view of the X-ray detector 200.

As described above, the X-ray detector 200 used in the X-ray apparatus100 may be implemented as a portable X-ray detector. In this case, theX-ray detector 200 may be equipped with a battery for supplying power tooperate wirelessly, or as shown in FIG. 2, may operate by connecting acharge port 201 to a separate power supply via a cable C.

A case 203 maintains an external appearance of the X-ray detector 200and has therein a plurality of detecting elements for detecting X-raysand converting the X-rays into image data, a memory for temporarily orpermanently storing the image data, a communication module for receivinga control signal from the X-ray apparatus 100 or transmitting the imagedata to the X-ray apparatus 100, and a battery. Furthermore, imagecorrection information and intrinsic identification (ID) information ofthe X-ray detector 200 may be stored in the memory, and the stored IDinformation may be transmitted together with the image data duringcommunication with the X-ray apparatus 100.

FIG. 3 is a block diagram of an X-ray apparatus 100 according to anembodiment.

Referring to FIG. 3, the X-ray apparatus 100 according to the presentembodiment may include an X-ray radiation device 305, a controller 310,a power supply 320 including a lithium ion battery 322, and a charger330. The X-ray apparatus 100 may further include a high voltagegenerator (not shown) provided on a main body. The X-ray apparatus 100of FIG. 3 may be implemented as a mobile X-ray apparatus as shown inFIG. 1, and FIG. 3 illustrates only components related to the presentembodiment. Thus, it will be understood by those of ordinary skill inthe art that the X-ray apparatus 100 may further include commoncomponents other than those shown in FIG. 3.

The descriptions with respect to the X-ray radiation device 110 in FIG.1 may apply to descriptions with respect to the X-ray radiation device305, and thus, are not repeated. Furthermore, the descriptions withrespect to the controller 120 in FIG. 1 may apply to descriptions withrespect to the controller 310, and thus, are not repeated.

The power supply 320 may supply power to a load via the lithium ionbattery 322. For example, the load may include the X-ray radiationdevice 305, the controller 310, and various other components of theX-ray apparatus 100, to which power is supplied. In other words, thelithium ion battery 322 may supply operating power to the X-rayradiation device 305 and the controller 310.

Furthermore, the power supply 320 may supply, via the lithium ionbattery 322, operating power to components of the X-ray apparatus 100that require the operating power. For example, the power supply 320 maysupply operating power to the input device 151, the display 152, and thecommunication unit 140 of the X-ray apparatus 100 via the lithium ionbattery 322.

The power supply 320 may control overcurrent that occurs during emissionof X-rays by the X-ray radiation device 305. In other words, as theX-ray radiation device 305 emits X-rays, overcurrent that is higher thana normal operating current may flow in the power supply 320, and thepower supply 320 may control the overcurrent. According to anembodiment, in order to control overcurrent, the power supply 320 mayconstruct a circuit consisting of a discharge field effect transistor(FET) having FETs connected in parallel and a charge FET. According toanother embodiment, in order to control the overcurrent, the powersupply 320 may construct a circuit including current sensors havingdifferent capacities for measuring the amount of discharge current.

The charger 330 may charge the power supply 320. In detail, the charger330 may supply a charging power to charge the lithium ion battery 322 ofthe power supply 320. In this case, the charging power may be a powergenerated by the charger 330. According to an embodiment, the charger330 may be combined with an external power supply to receive power fromthe external power supply. The charger 330 may then control the receivedpower according to a user input or arithmetic operations performedwithin the X-ray apparatus 100, to supply a charging power to thelithium ion battery 322.

The power supply 320, the charger 330, and the controller 310 may eachinclude a communication interface that enables communicationtherebetween. For example, the power supply 320, the charger 330, andthe controller 310 may communicate with one another via theircommunication interfaces according to a controller area network (CAN)protocol. Furthermore, according to another embodiment, communicationsmay be performed among the power supply 320, the charger 330, and thecontroller 310 by using a high-speed digital interface such as lowvoltage differential signaling (LVDS), an asynchronous serialcommunication protocol such as a universal asynchronous receivertransmitter (UART), a low-latency network protocol such as an errorsynchronous serial communication protocol, or other variouscommunication methods that are obvious to those of ordinary skill in theart. Furthermore, the power supply 320, the charger 330, and thecontroller 310 may each be constituted by a different module. Thus,since the controller 310 does not need to directly monitor a highvoltage, a high voltage circuit is not needed within the controller 310.This may consequently reduce the risks associated with the high voltagecircuit, thereby effectively improving stability.

In detail, in a mobile X-ray apparatus using a conventional lead-acidbattery, a controller may include a circuit for monitoring a highvoltage state, and may be damaged by high voltages. On the other hand,in the X-ray apparatus 100 according to the present embodiment, a BMS ofthe power supply 320 may monitor a high voltage state and transmit thehigh voltage state to the controller 310. This configuration may reducethe risk of damage to the controller 310.

Furthermore, when the power supply 320, the charger 330, and thecontroller 310 are each composed of a different module, they may be usedfor different mobile X-ray apparatuses and thus share a common platform.Furthermore, by applying a shield case to each of the power supply 320,the charger 330, and the controller 310, it is possible to suppressElectro Magnetic Interference (EMI)/Electro Magnetic Compatibility (EMC)noise that may occur therebetween.

FIG. 4 illustrates components of a power supply 320 included in a mobileX-ray apparatus 100, according to an embodiment.

Referring to FIG. 4, the power supply 320 may include a lithium ionbattery 322, a BMS 410, a discharge FET 430, and a charge FET 440. Thepower supply 320 shown in FIG. 4 includes only components related to thepresent embodiment. Furthermore, the power supply 320 may include avoltage sensor (not shown) for detecting a voltage and a temperaturesensor (not shown) for detecting a temperature. Thus, one of ordinaryskill in the art will understand that the power supply 320 may furtherinclude common components other than those shown in FIG. 4.

The lithium ion battery 322 is a type of secondary battery and consistsof three components: an anode, a cathode, and an electrolyte. Forexample, lithium cobalt oxide (LiCoO₂) or lithium iron phosphate(LiFePO₄) may be used for the anode, and graphite may be used for thecathode. The lithium ion battery 322 may include a combination of aplurality of battery cells connected to each other. For example, thelithium ion battery 322 may include a total of 352 cells, e.g., a serialconnection of 88 cells which are connected in parallel as 4 strings,e.g., 4 parallel cell groups each including 88 serially connected cells.

Furthermore, the lithium ion battery 322 may be suitable for use in amobile X-ray apparatus due to its smaller size and lighter weight thanconventional lead-acid batteries. For example, since a total weight ofthe power supply 330 including the lithium ion battery 322 and aperipheral circuit may be 33.2 kg, the total weight may be less than 35kg, which is the maximum allowable gross weight for carrying on anaircraft. Thus, the power supply 320 may be transported by air as asingle component.

The mobile X-ray apparatus 100 may supply power to an X-ray radiationdevice 305 through a battery, and may include the BMS 410 configured tooperate a protection circuit by checking a voltage and a temperature ofthe battery.

The BMS 410 may detect a state of the lithium ion battery 322, such as avoltage and a temperature thereof. According to an embodiment, the BMS410 may include a battery stack monitor circuit designed to monitor avoltage of the lithium ion battery 322 and a temperature of a batterycell. The BMS 410 may control and manage the power supply 320 based onthe state of the lithium ion battery 322. Furthermore, the BMS 410 maycontrol on/off states of the charge FET 440 and the discharge FET 430 tomanage a charge path and a discharge path, respectively.

Furthermore, the BMS 410 may operate a protection circuit based on thestate of the lithium ion battery 322. In other words, the BMS 410 mayoperate, based on the state of the lithium ion battery 322, theprotection circuit to protect the lithium ion battery 322 from dangerousconditions. In detail, based on the state of the lithium ion battery322, the BMS 410 may operate the protection circuit to protect thelithium ion battery 322 against at least one of over-discharge,overcurrent, overheating, and unbalancing between battery cells.

The BMS 410 may operate, based on the state of the lithium ion battery322, the protection circuit by checking states of over-discharge,overcurrent, overheating, and unbalancing between battery cells, and mayaccordingly be shut down.

The BMS 410 may operate the protection circuit when the lithium ionbattery 322 is in an over-discharged state where a voltage of thelithium ion battery 322 is lower than a reference voltage. For example,if a voltage of the lithium ion battery 322 drops to less than or equalto 275 V, the BMS 410 may operate a shutdown circuit to turn itself off.Furthermore, the BMS 410 may operate the protection circuit when thelithium ion battery 322 is in an overcurrent state where a current ofthe lithium ion battery 322 is higher than a reference value. Forexample, if the current of the lithium ion battery 322 is greater thanor equal to 40 A, the BMS 410 may operate a shutdown circuit to resetitself. The BMS 410 may also operate the protection circuit when thelithium ion battery 322 is in an overheated state where a temperature ofthe lithium ion battery 322 is higher than a reference value. Forexample, if the temperature of the lithium ion battery 322 is greaterthan or equal to 70° C., the BMS 410 may operate the protection circuitto shut off a charge path and a discharge path. Furthermore, when thelithium ion battery 322 is unbalanced between cells, the BMS 410 mayoperate the protection circuit. For example, if a voltage differencebetween cells in the lithium ion battery 322 remains greater than orequal to 0.5 V for ten (10) seconds or more, the BMS 410 may operate ashutdown circuit to turn itself off.

The BMS 410 may communicate with a controller 310 via a communicationinterface 412, e.g., according to a CAN protocol. Further, the charger330 may communicate with the controller 310 via a communicationinterface 414, e.g., according to the CAN protocol.

A load 406 may receive power via a charge path and/or a discharge path.

The discharge FET 430 may include a plurality of FETs 432 connected inparallel. Since overcurrent may flow in the power supply 320 duringX-ray emission by the X-ray radiation device 305, the FETs having aspecific capacity in the discharge FET 430 may be connected in parallel.In other words, by connecting the FETs having the specific capacity inparallel, a maximum allowable current capacity of the discharge FET 430may be increased. For example, if overcurrent greater than or equal to300 A flows within the power supply 320 during X-ray emission by theX-ray radiation device 305, the discharge FET 430 may include 4 FETswhich are connected in parallel and have a capacity of 100 A each forthe protection against the overcurrent.

According to an embodiment, the discharge FET 430 and the charge FET 440may each be constituted by an N-channel FET.

The discharge FET 430 and the charge FET 440 may control a path ofdischarge or charge current when the lithium ion battery 322 isdischarged or charged. According to an embodiment, when the lithium ionbattery 322 is discharged, the charge FET 440 may be turned off, and adischarge current loop may be formed by the discharge FET 430. Accordingto another embodiment, when the lithium ion battery 322 is charged, thedischarge FET 430 may be turned off, and a charge current loop may beformed by a diode or diodes 434 included in the discharge FET 430 andthe charge FET 440. Furthermore, the lithium ion battery 322 may bedischarged and charged at the same time via the discharge FET 430 andthe charge FET 440.

Furthermore, while FIG. 4 shows that a load 406 for receiving a powerfrom the lithium ion battery 322 includes the controller 310 and theX-ray radiation device 305, the load 406 may further include othercomponents of the X-ray apparatus 100 that require power.

FIG. 5 is a schematic diagram illustrating discharging of a lithium ionbattery 322 according to an embodiment.

An on/off state of a discharge FET 430 may be controlled based on asignal output from a BMS 410. In detail, the discharge FET 430 may beturned on when the lithium ion battery 322 is discharged and be turnedoff when the lithium ion battery 322 is charged. The signal may becoupled to a gate terminal of the discharge FET 430. When the dischargeFET 430 is turned off, a current path is formed from a minus terminal ofthe lithium ion battery 322 to a charger 330 via a body diode.

In detail, when the lithium ion battery 322 is discharged, a charge FET440 may be turned off since a source (S) voltage of the charge FET 440is higher than a drain (D) voltage thereof. Furthermore, when thelithium ion battery 322 is discharged, a discharge FET 430 may be turnedon since a drain (D) voltage of the discharge FET 430 is higher than asource (S) voltage thereof.

Thus, as shown in FIG. 5, a discharge current loop may be formed in aclockwise direction in which a discharge current flows through a load406, the discharge FET 430, and the lithium ion battery 322.Furthermore, even when the charge FET 440 is turned off, discharging ofthe lithium ion battery 322 may be performed normally.

FIG. 6 is a schematic diagram illustrating charging of a lithium ionbattery 322 according to an embodiment.

An on/off state of a charge FET 440 may be controlled based on a signaloutput from a BMS 410. In detail, the charge FET 440 may be turned onwhen the lithium ion battery 322 is charged and be turned off when thelithium ion battery 322 is discharged. When the charge FET 440 is turnedoff, a current path from the load 406 to a minus terminal of the lithiumion battery 322 may be formed.

In detail, when the lithium ion battery 322 is charged, a discharge FET430 may be turned off since a source (S) voltage of the discharge FET430 is higher than a drain (D) voltage thereof. When the discharge FET430 is turned off, a charge current may flow through a body diode of thedischarge FET 430. Furthermore, when the lithium ion battery 322 ischarged, the charge FET 440 may be turned on since a drain (D) voltageof the charge FET 440 is higher than a source (S) voltage thereof.

Thus, as shown in FIG. 6, a charge current loop may be formed in acounter-clockwise direction in which a charge current flows through acharger 330, the lithium ion battery 322, a diode 434 of the dischargeFET 430, and the charge FET 440. Furthermore, even when the dischargeFET 430 is turned off, charging of the lithium ion battery 322 may beperformed normally.

FIG. 7 is a detailed block diagram of a mobile X-ray apparatus 100according to an embodiment.

Referring to FIG. 7, a power supply 320 may include a lithium ionbattery 322, a BMS 410, a discharge FET 430, a charge FET 440, ashutdown circuit 710, a first current sensor 730, a second currentsensor 740, a DC-to-DC (DC-DC) converter 720, and a fuse 760.Furthermore, the X-ray apparatus 100 may include a third current sensor751. Since the lithium ion battery 322, the BMS 410, the discharge FET430, and the charge FET 440 respectively correspond to the lithium ionbattery 322, the BMS 410, the discharge FET 430, and the charge FET 440described with reference to FIG. 4, detailed descriptions thereof willbe omitted below. The first and second current sensors 730 and 740 mayinclude a Hall sensor, and the shutdown circuit 710 that is a protectioncircuit may include a switching circuit such as a FET.

The BMS 410 may detect current of the lithium ion battery 322 by usingdifferent current sensors, i.e., the first and second current sensors730 and 740. In detail, the BMS 410 may detect current flowing in thelithium ion battery 322 by using the first current sensor 730. The firstcurrent sensor 730 may be a small-capacity sensor for detecting acurrent having a relatively low intensity. In other words, the firstcurrent sensor 730 may be a sensor for detecting a current having anintensity less than or equal to a reference level. For example, thefirst current sensor 730 may detect a current that is less than or equalto 50 A. Furthermore, when overcurrent flows in the lithium ion battery322, the BMS 410 may detect overcurrent flowing in the lithium ionbattery 322 by using the second current sensor 740. The second currentsensor 740 may be a large-capacity sensor for detecting a current havinga relatively high intensity. In other words, the second current sensor740 may be a sensor for detecting a current having an intensity greaterthan or equal to a reference level. For example, the second currentsensor 740 may detect a current that is greater than or equal to 300 A.

According to an embodiment, the BMS 410 may detect, via the firstcurrent sensor 730, current flowing in the lithium ion battery 322 byactivating the first current sensor 730 while deactivating the secondcurrent sensor 740. Then, when an X-ray radiation device 305 emitsX-rays, the BMS 410 may detect overcurrent that occurs during the X-rayemission via the second current sensor 740 by activating the secondcurrent sensor 740 while deactivating the first current sensor 730.Subsequently, when the X-ray emission is completed, the BMS 410 maydetect, via the first current sensor 730, current flowing in the lithiumion battery 322 by activating the first current sensor 730 whiledeactivating the second current sensor 740. According to an embodiment,the BMS 410 may receive an X-ray emission preparation signal from acontroller 310 and activate the second current sensor 740 to detectovercurrent occurring during X-ray emission via the second currentsensor 740.

The BMS 410 may check the residual amount of the lithium ion battery 322based on the amount of current detected using the first and secondcurrent sensors 730 and 740. In detail, the BMS 410 may use CoulombCounting Based Gauging to check the residual amount of the lithium ionbattery 322 based on the detected amount of current.

Furthermore, the mobile X-ray apparatus 100 may further include thethird current sensor 751 for measuring a charge current. In other words,the mobile X-ray apparatus 100 may further include the third currentsensor 751 at an output terminal 752 of the charger 330. When thelithium ion battery 322 is charged and discharged at the same time,current measured by the first or second current sensor 730 or 740 may bea sum of a discharge current and a charge current. Thus, in order toaccurately measure a discharge current and a charge current, the mobileX-ray apparatus 100 may measure the charge current by using the thirdcurrent sensor 751.

The BMS 410 may receive signals indicating that the X-ray radiationdevice 305 starts emission of X-rays and that the X-ray radiation device305 completes the emission of X-rays from the controller 310 via acommunication interface 412.

The BMS 410 may output a first signal based on a state of the lithiumion battery 322. The first signal may be a shutdown signal that isapplied to the shutdown circuit 710. The BMS 410 may turn itself off byusing the shutdown circuit 710. When the BMS 410 checks a state of thelithium ion battery 322 to detect hazardous conditions such asover-discharge and overcharge, the BMS 410 may turn itself off by usingthe shutdown circuit 710 that serves as a protection circuit. When theBMS 410 turns itself off, power being supplied to the controller 310 isalso cut off, so that the controller 310 may also turn off.

The fuse 760 is designed to stop continuous flowing of excessive currentthat is greater than a nominal value in the power supply 320 and mayprotect a battery cell when the lithium ion battery 322 is subjected toan external short circuit.

The DC-DC converter 720 may convert power supplied by the lithium ionbattery 322 into a DC power for driving the BMS 410.

FIG. 8 illustrates a shutdown process performed by the mobile X-rayapparatus 100 according to an embodiment. The shutdown process will nowbe described with reference to FIGS. 7 and 8.

Referring to FIGS. 7 and 8, the power supply 320, the controller 310,and the charger 330 may each include a communication interface andcommunicate with one another via their communication interfaces. Forexample, the power supply 320, the controller 310, and the charger 330may communicate with one another according to a CAN protocol.

The power supply 320 may include a first temperature sensor 820.According to an embodiment, the power supply 320 may include the firsttemperature sensor 820 that is dedicated for use with the BMS 410 andmay be directly monitored by the BMS 410. The BMS 410 may use the firsttemperature sensor 820 to monitor a temperature of the power supply 320and determine whether the power supply 320 is overheated. For example,if the power supply 320 is overheated to a temperature higher than aspecific threshold value, the BMS 410 may control the charge FET 440that is a charge controller and the discharge FET 430 that is adischarge controller to cut off a charge path and a discharge path andcontrol a protection circuit to turn off the BMS 410 itself.

Furthermore, the power supply 320 may further include a secondtemperature sensor 810. According to an embodiment, the power supply 320may include the second temperature sensor 810 that is dedicated for usewith the controller 310 and may be directly monitored by the controller310. The second temperature sensor 810 may be provided on outside of theBMS 410. If a communication error occurs between the controller 310 andthe BMS 410, the controller 310 may not be able to receive temperatureinformation of the power supply 320 from the BMS 410. In this case, thecontroller 310 may monitor the temperature of the power supply 320 viathe second temperature sensor 810. Thus, when a communication erroroccurs, the controller 310 may determine whether to turn off the powersupply 320 by using the second temperature sensor 810 regardless of thestate of the BMS 410.

The power supply 320 and the charger 330 may respectively includeinterrupt pins 831 and 833 that can be directly controlled by thecontroller 310. In other words, the controller 310 may respectivelytransmit disable signals to the power supply 320 and the charger 330 viathe interrupt pins 831 and 833, and accordingly turn off the powersupply 320 and the charger 330. Thus, when it is determined that atemperature of the power supply 320 is equal to or higher than aspecific threshold value via the second temperature sensor 810, thecontroller 310 may forcibly turn off the power supply 320 and thecharger 330 via the interrupt pins 831 and 833, respectively.

Furthermore, when the BMS 410 operates a shutdown circuit that is aprotection circuit to turn itself off, a shutdown signal from the BMS410 may be transmitted to the controller 310. After receiving theshutdown signal, the controller 310 may monitor whether the BMS 410 isshut down for a specific amount of time. If the BMS 410 is not shut downfor the specific amount of time as a result of monitoring, thecontroller 310 may forcibly turn off the BMS 410 via the interrupt pin831. For example, after the BMS 410 activates a shutdown bit, thecontroller 310 may monitor whether the BMS 410 is shut down for ten (10)seconds. If the BMS 410 is not shut down for 10 seconds, the controller310 may forcibly turn off the BMS 410 via the interrupt pin 831.

FIG. 9 illustrates an X-ray apparatus according to an exemplaryembodiment.

According to an exemplary embodiment, the charger 330 may include awireless charging system including a transmitting module 920, e.g., atransmitter, and a receiving module 910, e.g., a receiver. For example,the charger 330 may be a self-inductive wireless charging system. In thecharger 330, the transmitting module 920 may convert an AC power from anexternal power supply into a DC power, amplify the DC power, andtransmit the amplified DC power wirelessly to the receiving module 910via a transmitting coil. The receiving module 910 may rectify thereceived power to charge the lithium ion battery 322.

As another example, the receiving module 910 of the charger 330 mayreceive a power transmitted wirelessly by the transmitting module 920installed externally to the receiving module 910 and may rectify thereceived power to charge the lithium ion battery 322. Thus, an X-rayapparatus 100 including the charger 330 may be located near thetransmitting module 920 and may charge the lithium ion battery 322 byusing the power transmitted wirelessly by the transmitting module 920.

FIG. 10 is a timing diagram of an operation of charging a lithium ionbattery 322 according to an exemplary embodiment.

First, during interval A, as the charger 330 performs a chargingoperation, a charge voltage may increase while a charge current remainsconstant.

Thereafter, during interval B, as the lithium ion battery 322 relaxes,the charge current may decrease.

An interval C indicates a low current state in which a charge currentless than a specific threshold value remains for a specific amount oftime. The charger 330 may detect the low current state, as will bedescribed in detail below with reference to FIG. 11. If the low currentstate is detected for a specific amount of time or a specific number oftimes, the charger 330 may stop a charging operation. For example, ifthe charger 330 detects a low current state, in which the charge currentis less than or equal to 0.5 A, 10 times, the charger 330 may stop acharging operation. Thus, if the lithium ion battery 322 relaxes, thecharger 330 may stop the charging operation, thereby preventingunnecessary power consumption.

Subsequently, during interval D, when a voltage of the lithium ionbattery 322 drops to a preset value, the charger 330 may restart thecharging operation, and the charge current may also increase.

Thereafter, during interval E, which corresponds to the interval A, asthe charger 330 performs the charging operation, the charge voltage mayincrease while the charge current remains constant.

FIG. 11 is a flowchart of a method of sensing of a low current state bythe charger 330, according to an exemplary embodiment.

The charger 330 may detect a charge current value (operation S1101).

The charger 330 may determine whether the detected charge current valueis less than an upper off-state charge current threshold (operationS1103). For example, the upper off-state charge current may be 0.5 A.

If the detected charge current value is less than the upper off-statecharge current threshold in operation S1103, the charger 330 mayincrease a low current count value by 1 (operation S1105). In otherwords, if the low current count value is increased by 1 each cycle toreach a certain count value, e.g., 10, the charger 330 may determinethat the current has remained low for a certain amount of time.

Otherwise, if the detected charge current value is not less than theupper off-state charge current threshold in operation S1103, the charger330 may determine whether the detected charge current value is greaterthan a lower on-state charge current threshold (operation S1107). Forexample, the lower on-state charge current threshold may be 0.8 A.

If the detected charge current value is greater than the lower on-statecharge current threshold in operation S1107, the charger 330 may set thelow current count value to 0 (operation S1109).

Otherwise, if the detected charge current value is not greater than thelower on-state charge current threshold in operation S1107, the charger330 may detect a charge current value (operation S1101).

The charger 330 may determine whether the low current count value isfive 5 (operation S1111).

If the low current count value is 5 in operation S1111, the charger 330may generate a signal indicating that a charging operation is to bestopped after a lapse of a certain amount of time (operation S1113).

Otherwise, if the low current count value is not 5 in operation S1111,the charger 330 may determine whether the low current count value is 10(operation S1115).

If the low current count value is 10 in operation S1115, the charger 330may stop the charging operation (operation S1117). In other words, ifthe low current count value is 10, the charger 330 may determine thatthe low current state has remained for the certain amount of time andthen stop the charging operation.

Otherwise, if the low current count value is not 10 in operation S1115,the charger 330 may detect a charge current value (operation S1101).

FIG. 12 is an external/internal perspective view of an X-ray apparatus100 according to an embodiment.

Referring to FIG. 12, a power supply 320 and a charger 330 are arrangedinside the X-ray apparatus 100.

The power supply 320 weighs approximately 33.2 kg and may be arranged ina lower part of the X-ray apparatus 100. Thus, since a center of gravityof the X-ray apparatus 100 may be located at the bottom thereof, theX-ray apparatus 100 may be moved stably.

The power supply 320 may be encased in a metal case and be provided as amodule that is physically separated from other components.

An internal structure of the power supply 320 will be described indetail below with reference to FIGS. 20 through 25.

The charger 330 receives an AC power to charge a lithium ion batterywithin the power supply 320. The charger 330 may be shielded by a shieldcase and provided as a separate module. The charger 330 may bepositioned at a front surface of the power supply 320.

FIG. 13 is an external/internal perspective view of an X-ray apparatus100 taken from a different angle, according to an embodiment.

Referring to FIG. 13, a power supply 320 and a charger 330 are arrangedinside the X-ray apparatus 100.

Since the power supply 320 and the charger 330 are arranged in the samemanner as described with reference to FIG. 12, a detailed descriptionthereof will be omitted below.

FIG. 14 illustrates a state in which a power supply 320 is detached froman X-ray apparatus 100, according to an embodiment.

The power supply 320 may include a handle 1401 and may be detached froma main body 101 of the X-ray apparatus 100. A user may use the handle1401 to separate the power supply 320 from or mount it into the mainbody 101 of the X-ray apparatus 100. The power supply 320 may includetwo handles 1401 that allow the user to separate the power supply 320from the main body 101 or lift and move the power supply 320.

For example, the user may pull the power supply 320 along a K direction1402 and separate it from the main body 101.

FIG. 15 is an external/internal plan view of an X-ray apparatus 100according to an embodiment.

Referring to FIG. 15, the X-ray apparatus 100 includes wheels 1301 and1403, a power supply 320, and a charger 330.

The power supply 320 may be provided between the wheels 1301 and 1403,so that a width W1 1405 of the X-ray apparatus 100 may be decreased.Furthermore, a width W2 1407 of the power supply 320 may be less thanthe width W1 1405.

FIG. 16 is an external view of a power supply 320 according to anembodiment.

Referring to FIG. 16, the power supply 320 may include an external case1600, a discharging terminal 1601, a charging terminal 1603, a firstcommunication connector 1605, a second communication connector 1607, andhandles 1609 and 1610.

The external case 1600 may be made of metal, and protect the powersupply 320 against external shocks and function as a shield case thatblocks electromagnetic waves from entering or exiting the power supply320.

The discharging terminal 1601 is connected to a cable 1601 a to supplypower output from a battery cell in the power supply 320 to an X-rayradiation device.

The charging terminal 1603 is connected to a charging power supplyterminal (1801 of FIG. 18) of a charger (330 of FIG. 18) and a cable1603 a to receive power necessary for charging a battery.

The second communication connector 1607 is connected to a charger and acontroller via a cable (not shown) so that the power supply 320 mayperform communications with the charger and the controller. For example,the power supply 320 may communicate with the charger and the controlleraccording to a CAN protocol via the cable connected to the secondcommunication connector 1607.

Furthermore, the user may use the second communication connector 1607and the cable to update firmware for the power supply 320 withoutseparating the power supply 320 from an X-ray apparatus. For example,when the power supply 320 is mounted into the X-ray apparatus, the usermay transmit data necessary to update the firmware for the power supply320 via the controller of the X-ray apparatus.

The power supply 320 may include the first communication connector 1605that is, for example, a RS232C port. When the power supply 320 isseparated from the X-ray apparatus, the firmware for the power supply320 may be updated via the first communication connector 1605.

Handles 1609 and 1610 may be folding handles, but are not limitedthereto. Various types of handles may be used as the handles 1609 and1610. Examples of the handles 1609 and 1610 may include permanentmagnetic handles, removable handles, handles using concave portionsformed in the external case 1600, outward-protruding handles, etc.Furthermore, while FIG. 16 shows that the power supply 320 is equippedwith the two handles 1609 and 1610, the number of handles may varyaccording to embodiments.

FIG. 17 is an example of a controller 310 according to an embodiment.

The controller 310 may be composed of a plurality of printed circuitboards (PCBs).

The controller 310 may include various blocks for operating an X-rayapparatus.

In particular, the controller 310 may include a third communicationconnector 1701 and a fourth communication connector 1703 forrespectively performing communications with the power supply (320 ofFIG. 16) and the charger (330 of FIG. 18).

The third communication connector 1701 is connected to the secondcommunication connector (1607 of FIG. 16) of the power supply 320 sothat the controller 310 may communicate with the power supply 320according to a CAN protocol.

The fourth communication connector 1703 is connected to a fifthcommunication connector (1803 of FIG. 18) of the charger 330 so that thecontroller 310 may communicate with the charger 330 according to the CANprotocol.

FIG. 18 is an external view of the charger 330 according to anembodiment.

Referring to FIG. 18, the charger 330 may include an external case 1800,the fifth communication connector 1803, and the charging power supplyterminal 1801.

The external case 1800 may be made of metal, and protect the charger 330against external shocks and serve as a shield case that blockselectromagnetic waves from entering or exiting the charger 330. Thefifth communication connector 1803 is connected to the fourthcommunication connector (1703 of FIG. 17) of the controller (310 of FIG.17) so that the charger 330 may communicate with the controller 310according to a CAN protocol. Furthermore, the charger 330 may update itsfirmware via the fifth communication connector 1803.

The charging power supply terminal 1801 may supply power to the chargingterminal (1603 of FIG. 16) of the power supply 320.

FIG. 19 illustrates a state in which a power supply 320, a controller310, and a charger 330 are connected to one another, according to anembodiment.

Referring to FIG. 19, an X-ray apparatus may include the power supply320, the controller 310, and the charger 330.

A charging terminal 1603 of the power supply 320 is connected to acharging power supply terminal 1801 of the charger 330 via a cable toreceive power necessary to charge a battery cell (not shown) from thecharger 330.

The power supply 320, the controller 310, and the charger 330 areelectrically connected to one another via communication connectors andcables to perform communications therebetween according to a CANprotocol.

For example, a second communication connector 1607 may be connected to athird communication connector 1701 of the controller 310 via a cable1901. A fourth communication connector 1703 of the controller 310 may beconnected to a fifth communication connector 1803 of the charger 330 viaa cable 1903.

The power supply 320, the controller 310, and the charger 330 maytransmit or receive data by performing communications therebetweenaccording to the CAN protocol.

The X-ray apparatus may use second through fifth communicationconnectors 1607, 1710, 1703, and 1803 to update the power supply 320 andthe charger 330. When the power supply 320 and the charger 330 areupdated via the second through fifth communication connectors 1607,1710, 1703, and 1803, firmware for the power supply 320 and firmware forthe charger 330 may be respectively transmitted to the power supply 320and the charger 330 via a system board. This eliminates the need forseparating the power supply 320 and the charger 330 from the X-rayapparatus.

According to embodiments, the power supply 320, the controller 310, andthe charger 330 may be connected using wireless communication.

FIG. 20 illustrates an internal structure of a power supply 320according to an embodiment.

Referring to FIG. 20, the power supply 320 may include a shutdowncircuit 2001, a master BMS circuit 2002, an FET 2003, a wake up button2004, a slave BMS circuit 2005, a fuse 2006, and a BMS switch 2007.

Since the components 2001 through 2006 perform the same functions astheir counterparts described with reference to FIGS. 4 through 7,detailed descriptions of the functions will be omitted below.

A structure in which the components are arranged along an M direction2010 will now be described.

The shutdown circuit 2001 may be positioned in an upper right side ofthe power supply 320.

The master BMS circuit 2002 may be positioned in an upper middle portionof the power supply 320 and adjacent to the shutdown circuit 2001. Sincethe shutdown circuit 2001 is located close to the master BMS circuit2002, a cable connecting the shutdown circuit 2001 to the master BMScircuit 2002 may be shortened, and accordingly radiation noise may bereduced.

The shutdown circuit 2001 and the master BMS circuit 2002 may bearranged parallel to a top surface (not shown) of an external case ofthe power supply 320. Due to this arrangement, electromagnetic noiseradiated from an integrated circuit (IC) of the master BMS circuit 2002in a vertical direction may be shielded by the top surface of theexternal case.

The FET 2003 may be arranged on a left side of the master BMS circuit2002.

The wake up button 2004 is positioned at a front portion of the externalcase. The wake up button 2004 may be a switch necessary for restarting asystem after a BMS is shut down.

The slave BMS circuit 2005 may be positioned in a lower left side of thepower supply 320. The slave BMS circuit 2005 may be arranged parallel toa front surface of the external case. A plurality of slave BMS circuits2005 may be arranged parallel to one another. For example, the slave BMScircuit 2005 may be constituted by eight (8) boards that are arrangedparallel to one another.

The BMS switch 2007 may supply or block power to a BMS circuit.

FIG. 21 is a cross-sectional view of a power supply 320 according to anembodiment.

In detail, FIG. 21 shows a cross-section of the power supply 320 takenalong the M direction (2010 of FIG. 20).

The power supply 320 may be encased in a metal case 2102.

The power supply 320 may be divided into four (4) regions.

Battery cells 2106 may be arranged in a lower right region of the powersupply 320. A structure of the battery cells 2106 will be described inmore detail below with reference to FIGS. 23 and 24.

A slave BMS circuit 2107 may be positioned in a lower left region of thepower supply 320.

A plurality of circuits 2103, i.e., a master BMS circuit, a shutdowncircuit, a DC-DC converter, and a protection circuit (an FET and a fuse)may be arranged in an upper right region of the power supply 320, whichis positioned above the battery cells 2106.

A plurality of components 2101, i.e., a power switch, a wake up switch,and a CAN board may be arranged in an upper left region of the powersupply 320, which is positioned above the slave BMS circuit 2107.

The battery cells 2106 and the slave BMS circuit 2107 are separated by apartition wall 2105 so that a liquid leaking from the battery cells 2106may not flow into the slave BMS circuit 2107. The partition wall 2105may be constituted by a frame made of an insulation material, but is notlimited thereto.

The battery cells 2106 and the plurality of circuits 2103 are separatedby a partition wall 2104 so that a liquid leaking from the battery cells2106 may not flow into the plurality of circuits 2103, i.e., the masterBMS circuit, the shutdown circuit, the DC-DC converter, and theprotection circuit (the FET and the fuse). The partition wall 2104 maybe constituted by a frame made of an insulation material, but is notlimited thereto.

FIG. 22 is a block diagram of a configuration of a BMS circuit accordingto an embodiment.

The BMS circuit may include a slave BMS circuit 2201 and a master BMScircuit 2203.

The slave BMS circuit 2201 may manage voltages, temperatures, andunbalancing between cells of a battery pack with a number of cellgroups, e.g., eleven cell groups, connected in series.

For cell balancing, a resistor is used to discharge overcharged cellswhile charging other cells.

As described above with reference to FIG. 4, four (4) individual batterycells are connected in parallel to form a cell group, and eleven cellgroups are connected together in series to form a battery pack.

According to the embodiment, the BMS circuit includes eight (8) slaveBMS circuits 2201, but the number of slave BMS circuits 2201 may varydepending on the number of battery packs.

The slave BMS circuit 2201 may include a communication interface andcommunicate with the master BMS circuit 2203 via the communicationinterface to transmit voltages, temperatures, and information aboutunbalancing between cells of a battery pack to the master BMS circuit2203.

The master BMS circuit 2203 may collect information received from theeight slave BMS circuits 2201 to operate a protection circuit (notshown) and transmit the collected information to a system board via thecommunication interface (communication connector).

As described above, the slave BMS circuit 2201 manages a voltage and atemperature of battery cells and information about unbalancing betweenbattery cells in a dispersed manner, and the master BMS circuit 2203collects and manages them in an integrated manner. Due to thisconfiguration, a size of the master BMS circuit 2203 may be reduced. Inparticular, by dispersedly connecting cables respectively coupled tobattery cells to the slave BMS circuit 2201, it is possible tofacilitate arrangement of cables and accordingly, improve assemblycapabilities. Furthermore, if a problem occurs in the slave BMS circuit2201, only the faulty slave BMS circuit 2201 may be replaced. Thus,service efficiency may be enhanced.

FIG. 23 shows a state in which battery packs are mounted in a powersupply 320 according to an embodiment.

Referring to FIG. 23, upper and lower battery packs 2331 and 2333 aremounted in an external case 2300 of the power supply 320.

A reinforcement member 2301 is provided on one side of the external case2300.

The upper and lower battery packs 2331 and 2333 may be installed in theexternal case 2300 and stacked in two layers. A plurality of cables 2335may be connected to the upper and lower battery packs 2331 and 2333 inorder to connect the upper and lower battery packs 2331 and 2333 withslave BMS circuits (not shown).

A partition wall 2315 may be installed between the lower battery pack2333 and a bottom surface of the external case 2300.

A partition wall 2313 may be provided between the upper and lowerbattery packs 2331 and 2333.

A partition wall 2311 may be provided between the upper battery pack2331 and a region where a master BMS circuit (not shown) is positioned.

The partition walls 2311 and 2313 may be each formed of an insulationmaterial.

Furthermore, reinforcement members 2321 and 2323 may respectively beprovided on right and left sides of the upper and lower battery packs2331 and 2333. The reinforcement members 2321 and 2323 may protect theupper and lower battery packs 2331 and 2333 by preventing deformation ofthe external case 2300 caused by an external force.

The external case 2300 may be formed of a thick metal (e.g., with a 1.6tthickness) in order to protect the upper and lower battery packs 2331and 2333 and other main components of the power supply 320 against anexternal force.

In addition, for battery cells in a battery pack, lithium ion batterycells are used. Since a battery pack using lithium ion batteries isrelatively small and lightweight compared to a battery pack usinglead-acid batteries, a slim X-ray apparatus may be provided.

Due to the use of a lithium ion battery, a total weight of the powersupply 320 including battery cells and peripheral circuits does notexceed 35 kg, which is the maximum allowable gross weight for carryingon an aircraft. Thus, the power supply 320 may be transported by air asa single component.

FIG. 24 illustrates a structure of a battery pack 2331 according to anembodiment.

Referring to FIG. 24, the battery pack 2331 may include a cell group2401 and a battery holder 2402.

The cell group 2401 includes four battery cells connected in parallel.In other words, the four battery cells are connected together to formthe cell group 2401. Furthermore, eleven cell groups are connectedtogether in series to form the battery pack 2331.

The number of battery cells in a cell group and the number of cellgroups in a battery pack are merely an example, and may be adjusted tosuit an intended purpose.

The battery holder 2402 may accommodate and protect battery cells. Thebattery holder 2402 may be made of a flame retardant resin and has holes2403 formed therein for receiving the battery cells. The battery holder2402 may also be combined with another battery holder by a pin. Sincethe battery cells are housed in the battery holder 2402, even when abattery cell gets swollen, the swollen battery cell may not adverselyaffect another battery cell or component.

FIG. 25 illustrates a configuration of a slave BMS circuit 2500according to an embodiment.

Referring to FIG. 25, the slave BMS circuit 2500 may include atemperature sensor 2503 and a multi-cell battery stack monitor IC 2505.

The temperature sensor 2503 may detect temperatures of a battery cellhaving eleven cell groups connected in series. In detail, thetemperature sensor 2503 may be connected to a top and a bottom of fourbattery cells 2501 in each cell group to detect a temperature of thebattery cells in each cell group.

The temperature sensor 2503 detects temperatures of the 11 cell groupsand transmits the result to the multi-cell battery stack monitor IC2505.

As described above, a BMS circuit includes eight slave BMS circuits2500, each of which may transmit temperatures, voltages, and informationabout unbalancing between cells of a battery pack to a master BMScircuit via a communication interface.

FIG. 26 illustrates a structure in which a system board 2603 is mountedon a side of an X-ray apparatus, according to an embodiment.

Referring to FIG. 26, frames 2601 and 2605 and the system board 2603 areprovided on a side of the X-ray apparatus.

The system board 2603 may be a part of a controller.

The frames 2601 and 2605 may each have one side attached to a main body101 via a hinge and may be pivoted around a hinge axis.

As the frames 2601 and 2605 are pivoted around the hinge axis, aninternal system board mounted in the frames 2601 and 2605 may be exposedto outside the frames 2601 and 2605.

Circuit components 2606, 2607, 2608, and 2609 and the system board 2603may be mounted on the frames 2601 and 2605.

FIG. 27 illustrates a state in which the frames 2601 and 2605 of FIG. 26are open.

FIG. 27 shows the frames 2601 and 2605 and an internal system board2701.

The frames 2601 and 2605 may be pivoted around a hinge axis to be openedor closed in a transverse direction.

When the frames 2601 and 2605 open, the internal system board 2701 maybe exposed to outside. When a problem occurs in the internal systemboard 2701, the internal system board 2701 may be easily detached fromthe main body 101 by opening the frames 2601 and 2605 in the transversedirection. Accordingly, service efficiency may be increased.

While one or more embodiments have been described with reference to thefigures, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope of the present disclosure as definedby the following claims. Accordingly, the above embodiments and allaspects thereof are examples only and are not limiting.

What is claimed is:
 1. A mobile X-ray apparatus comprising: an X-rayradiation device; a controller configured to control the X-ray radiationdevice; a power supply configured to supply operating power to the X-rayradiation device and the controller via a lithium ion battery andcontrol the overcurrent which occurs during an X-ray emission by theX-ray radiation device; a charger configured to charge the lithium ionbattery; and a main body configured to house the controller, the powersupply, and the charger, wherein each of the controller, the powersupply, and the charger is embodied as a physically separate module, andwherein the power supply is encased in a metal case.
 2. The mobile X-rayapparatus of claim 1, wherein the power supply includes a master BMScircuit configured to operate a protection circuit against anovercurrent based on a state of the lithium ion battery, and the masterBMS circuit arranged parallel to a first surface of the metal case ofthe power supply.
 3. The mobile X-ray apparatus of claim 2, wherein thepower supply further includes shutdown circuit which is arrangedadjacent to the master BMS and parallel to a first surface of the metalcase of the power supply.
 4. The mobile X-ray apparatus of claim 2,wherein the power supply further includes a slave BMS circuit configuredto manage at least one voltage of the lithium ion battery, temperaturesof the lithium ion battery, and unbalancing between cells of the lithiumion battery, and the slave BMS circuit arranged parallel to a secondsurface of the metal case which is perpendicular to the first surface.5. The mobile X-ray apparatus of claim 2, wherein the power supplyfurther includes a slave BMS circuit configured to manage at least onevoltage of the lithium ion battery, temperatures of the lithium ionbattery, and unbalancing between cells of the lithium ion battery, andwherein the power supply further includes a partition wall which isformed of an insulation material is installed between the lithium ionbattery and the slave BMS circuit.
 6. The mobile X-ray apparatus ofclaim 1, wherein the power supply further includes a partition wallwhich is formed of an insulation material is installed between thelithium ion battery and the master BMS circuit.
 7. The mobile X-rayapparatus of claim 1, wherein the power supply includes a firstcommunication connector which performs communications with thecontroller, and the first communication connector configured to receivedata for updating a firmware of the power supply via the controller. 8.The mobile X-ray apparatus of claim 1, wherein the power supply includesat least one handle which is used to separate the power supply from themain body.
 9. The mobile X-ray apparatus of claim 1, wherein each of thecontroller, the power supply, and the charger respectively comprisescommunication connectors, and the controller, the power supply, and thecharger are configured to communicate with one another via respectivecommunication connectors according to a controller area network (CAN)protocol.
 10. The mobile X-ray apparatus of claim 1, wherein the powersupply and the charger respectively comprise interrupt pins that aredirectly controlled by the controller, and the controller is furtherconfigured to respectively turn off the power supply and the charger viathe interrupt pins.
 11. The mobile X-ray apparatus of claim 1, whereinthe charger is encased in a metal case which functions as a shieldblocking electromagnetic waves, and wherein the metal case of the powersupply and the metal case of the charger are installed separately fromeach other in the main body.
 12. A mobile X-ray apparatus comprising: anX-ray radiation device; a controller configured to control the X-rayradiation device; a power supply configured to supply operating power tothe X-ray radiation device and the controller via a lithium ion batteryand control the overcurrent which occurs during an X-ray emission by theX-ray radiation device; a charger configured to charge the lithium ionbattery; and a main body configured to house the controller, the powersupply, and the charger, wherein each of the controller, the powersupply, and the charger is embodied as a physically separate module, andwherein the charger is encased in a metal case.
 13. The mobile X-rayapparatus of claim 12, wherein the power supply includes a master BMScircuit configured to operate a protection circuit against anovercurrent based on a state of the lithium ion battery, and the masterBMS circuit arranged parallel to a first surface of the metal case ofthe power supply.
 14. The mobile X-ray apparatus of claim 13, whereinthe power supply further includes shutdown circuit which is arrangedadjacent to the master BMS and parallel to a first surface of the metalcase of the power supply.
 15. The mobile X-ray apparatus of claim 13,wherein the power supply further includes a slave BMS circuit configuredto manage at least one voltage of the lithium ion battery, temperaturesof the lithium ion battery, and unbalancing between cells of the lithiumion battery, and wherein the power supply further includes a partitionwall which is formed of an insulation material is installed between thelithium ion battery and the slave BMS circuit.
 16. The mobile X-rayapparatus of claim 12, wherein the power supply further includes apartition wall which is formed of an insulation material is installedbetween the lithium ion battery and the master BMS circuit.
 17. Themobile X-ray apparatus of claim 12, wherein the power supply includes afirst communication connector which performs communications with thecontroller, and the first communication connector configured to receivedata for updating a firmware of the power supply via the controller. 18.The mobile X-ray apparatus of claim 12, wherein each of the controller,the power supply, and the charger respectively comprises communicationconnectors, and the controller, the power supply, and the charger areconfigured to communicate with one another via respective communicationconnectors according to a controller area network (CAN) protocol.